Schiltknecht



March 1963 A. SCHILTKNECH-T 3,080,618

cums AND WEIGl-ITING APPARATUS FOR THE TOP ROLLS OF A DRAFTING ARRANGEMENT OF A SPINNING MACHINE Filed Sept. 6, 1960 3 Sheets-Sheet 1 Fly. 7

March 12, 1963 A, SCHILTKN HT 3,080,618

GUIDE AND WE TING APPARATUS FOR THE P ROLLS OF A DRAFTING RRANGEMENT OF A SPINN MACHINE3 Filed Sept. 6. 1960 Sheets-Shegt 2 v March 1963 A. SCHILTKNECHT 3,080,618

GUIDE AND WEIGHTING APPARATUS FOR THE TOP ROLLS OF A DRAFTING ARRANGEMENT OF A SPINNING MACHINE Filed Sept. 6, 1960 3 Sheets-Sheet 3 47 4951 2732513053 2 4; a I TTTfij $5 I HUIJ'IIL 54 A 26 2855 555253 25 Patented Mar. 12, 1963 3,630,618 GUEBE AND WEiG-HHNG APPARATUS FSR THE TSP RQLLS QT A DRAFTENG ARRANGEMENT F A Sll-INNTNG MAQHTNE Adoif ehilthnecht, Winterthur, Switzerland, assignor to Actiengeseilsehaft .l oh. .liaeob Rieter & (Zia, Winterthur, Switzerland, a corporation of fiwitzerland Fii d Sept. 6, 19%, Ser. No. 53,973 Claims priority, application Switzerland Sept. 11, 19 59 if (Ilaims. (Cl. 19-4267) The present invention relates to a guide and weighting apparatus for the top rolls of drafting arrangements in spinning machines.

The arms for guiding and weighting the top rolls of drafting arrangements must permit adjustment of the position of the pressure rolls to correspond to the character of the spinning material to be drafted whereby the weightin of the pressure rolls should be changed as little as possible. To produce this desired result, individually adjustably spring-loaded pressure roll carriers have been proposed. There is, however, usually not enough room for springs having the desired flat compression characteristic and producing the high pressure which are required in modern drafting arrangements. Springs having a steep compression characteristic are not suitable because there is too much difference in pressure if one pair of pressure rollers is more worn than another pair which is weighted by the same spring. Repeated grinding of the pressure rolls causes dilferences in diameter of the rolls whichnecessitates readjustments which consume time and are expensive.

Conventional drafting arrangements which are weighted by means of a lever or a centrally arranged spring have the disadvantage of changing the load or pressure distribution upon readjustment of the pressure saddles. These changes must either be disregarded or must be compensated by additional adjustments. it has been proposed to place the fulcrum of a load-distributing lever by means of conical pressure saddles so that a predetermined pressure distribution is maintained. In this case the involved two pairs of pressure rollers are simultaneously repositioned which is usually not desirable. Arrangements have been proposed in which the roller groups forming two drafting zones with a neutral zone therebetween are simultaneously readjusted in a predetermined relation whereby a substantially constant pressure is maintained on the top rollers. The last mentioned arrangement is objectionable, because the drafting zones cannot be readjusted independently of each other.

it is an object of the present invention to provide a weighting system for the top rollers of a drafting arrangement of a spinning machine which system overcomes the above described disadvantages of conventional systems by providing a weighting lever which is preferably placed inside a guide and weighting arm for the top rollers. The rear end of this weighting lever rests on an element transmitting a weighting force from a forceproducing means to the weighting lever. A pressure roll assembly is pivotally connected to the fore end of the weighting lever. A link supporting top roll guide means is pivotally connected to an intermediate part of the weighting lever and is pivotally connected to the guide and weighting arm.

The aforesaid pressure roll assembly comprises a spindle which is substantially parallel to the weighting lever and which extends through an element which is pivotally connected to the fore end of the weighting lever. A top roll holder is supported by the spindle forward of said element and a second top roll holder is supported by the spindle rearward of said element. The spindle is longitudinally displaceable in said element and in one of the holders, displaceability being afforded by threads on the spindle and in the element and in the holder. The pitches of the cooperating threads on the spindle and in the element and of the cooperating threads on the spindle and in the holder are different so that, upon rotation of the spindle for changing the distance between the holders, the leverage relation of the holders with respect to the swing fulcrum of the element is not changed.

The guide and weighting arm can be locked in the operating position in the conventional manner.

The apparatus according to the invention may be provided with means affording independent removal of the foremost pressure roll when the guide and weighting arm is swung down and locked. This means includes an elbow lever preferably located inside the forward end of the guide and weighting arm. The elbow lever has an arm whose end, upon swinging of the lever, extends below and engages suitable shoulders provided on the holder of the foremost pressure roll whereby the holder is tilted upon continued swinging of the elbow lever and the top roll can be removed.

With the apparatus according to the invention the weighting force applied to a plurality of top rolls by the same guide and weighting arm remains substantially the same even if the position and/or diameters of the top rolls relative to each other are considerably changed. In drafting arrangements having cradles for the upper aprons of double apron arrangements wherein the length of the cradle is between 40 mm. and mm. the deviations of the pressures acting on the intermediate pressure rolls and on the delivery pressure rolls at different adjustments of the spacing of the pressure rolls can be held below 18%. This is entirely satisfactory, particularly if the pressure acting on the back top roller is; maintained constant as is the case in the weighting system according to the invention.

The novel features which are considered characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, and additional objects and advantages thereof will best be understood from the following description of embodiments thereof when read in connection with the accompanying drawing, wherein:

FIG. 1 is a schematical longitudinal sectional view of a guide and Weighting apparatus according to the invention, the section being made along line 1-1 of FIG. 2.

FIG. 2 is a cross sectional view of a part of the guide and weighting apparatus shown in FIG. 1, the section being made along line IIII of said figure.

FIG. 3 is a part sectional side view of the forward portion of a guide and weighting apparatus of the general type schematically shown in FIGS. 1 and 2, in operating position.

FIG. 4 is a longitudinal sectional diagrammatic illustration of the forward part of a guide and weighting apparatus in position for removing the delivery roll held by the arm.

FIG. 5 is an enlarged sectional illustration of a part of a device for producing pressure and transmitting it to a weighting leverin the apparatus according to the invention.

FIG. 6 is a longitudinal sectional view of a modified.

saddle for the rear pressure rolls of a drafting arrangement.

Referring more particularly to FIG. 1 of the drawing, numeral 1 designates a tubular carrier which is rigidly connected to the frame of a spinning machine and extends longitudinally thereof. Regularly spaced supports 2 are mounted on the carrier 1, a guide and weighting arm 3 of inverted U-shaped cross section being swingably connected at 4 to each support 2. The arm 3, when in operating position, is locked in the conventional manner to the support 2 by means of a locking lever 5 having an arm to whose end a roller 6 is connected which is received in a slot 7 of the support 2 when the device is in locked position.

The weighting force is produced by means of a pressure fluid in a hose 8 placed inside the carrier 1 and longitudinally thereof. The pressure acting on the inside of the hose 8 is transmitted to a pressure shoe 9 resting on the hose 8 and connected to the end of one arm of an elbow lever 10 which is fulcrumed at 11 to the support 2.

A bracket 13 of inverted U-shaped cross sectional configuration is mounted inside the arm 3 between the vertical flanges 12 of the arm. The bracket 13 is provided with a longitudinal slot 14 receiving a screw 15 for connecting the bracket 13 to the arm 3. The slot 14 affords longitudinal displacement of the bracket 13 relative to the arm 3. A weighting lever is composed of parallel members 16 and 17 whose ends are interconnected and which are individually located between and parallel to the flanges 12 of the arm 3 and the flanges of the bracket 13. The

rear ends of the members 16 and 17 extend beyond the carrier 1 and are connected by a cylindrical element 19 resting on the elbow lever 10 (FIG. 5)-. An element 21 is pivotally connected at 21 to the forward ends of the members 16 and 17. The element 21 is provided with a threaded bore receiving a spindle 23 (FIG. 4) provided with a thread 22 fitting into the thread of the bore 20. The rear part of the spindle 23 is provided with a thread 24 whose pitch is different from the pitch of the thread 22 for purposes which will be explained later. The thread 24 fits the thread of a bore in a top roll holder 25 supported by the spindle 23 in the rear of the element 21. A fore top roll holder 26 is rotatable on the fore end of the spindle 23 but is prevented to move axially with respect to the spindle by means of an annular groove 27 in the spindle and a splint 28 extending through the holder. The forward end of the spindle 23 is provided with a slot 29 adapted to receive a screwdriver for revolving the spindle 23. The relation between the pitches of the threads 22 and 24 is such as to correspond to the relation of the distances between the element 21 and the holders 25 and 26. Therefore, the pressure roll holders 25 and 26 can be moved relative to the fulcrum 21' without changing the relation between the distances between the element 21 and the holders 25 and 26, and the holders 25 and 26 always receive the same fractions of the pressure exerted on the fulcrum 21', i.e., the weight on the holders is not changed unless the force transmitted by the weighting lever 16, 17 is changed.

A transverse rod 30 interconnecting the members 16 and 17 forms a fulcrum for a double link element 31 which 'extendsrearward and downward from the fulcrum and whose ends are connected .by a pin 32 swingably supporting a rail 33 which has a U-shaped cross section as shown in FIG. 2. The double link element 31 is pivotally connected by means of a transverse bolt 34 to the bracket 13. A bolt 35 extends through the forward ends of the flanges of the rail 33. A central element 36 has a forward end provided with a slot 37 receiving the bolt 35 and extends rearward and upward from the bolt 35. The rear end of the element.36 is also provided with a slot 38 which is parallel to the slot 37, the slot 38 receiving a bolt 39 which is rigidly connected to the bracket 13. The element 36 is thus horizontally slidable on the bolts 35 and 39. The link.31 and the central element 36 are swingably interconnected by means of a bolt 40. The element 36 which is operatively connected to the link 31, to the rail 33 and to the arm 3, through the bracket 13, guides the rail 33 to move parallel to itself upon'swinging of the link 31 on the ,arm 3.

As seen in FIG. 2, the rail 33 is provided with a longitudinal slot 41 for connecting a pressure roll holder 42 in a desired position along the rail 33. In this way the holder42 can be placed in any desired position on the rail 33 without changing thereactionof the force exerted by the pressure roll holder 42 on the rod 30. According to the invention all pressure reactions caused by the pressure rolls and acting on the weighting lever 16, 17 are independent of the position of the pressure rolls.

If the bracket 13 is somewhat displaced forwardly in order to increase the angle a formed by a vertical and a line connecting of the centers of the delivery top roll 43 and the drafting roll 44, the cylindrical element 19 is also moved forward whereby the lengths of the arm of the elbow lever 10 is shortened so that the force acting on the weighting lever 16, 17 is increased. As seen in FIG. 5, the active ength of the lever 10 is the distance between the center M of the fulcrum of the lever 10 and the point A where the element 19 rests on the lever 10. In order to maintain the loading force F constant, the surface 45 of the elbow lever 10 is curved so that the direction of the increased force P, to be transmitted at the point B, is changed and acts in a forwardly inclined direction, whereby the substantially vertical force component P which effects the weighting and is parallel to P is correspondingly smaller and remains with respect to greatness and direction equal to the force P. The surface 45 is shaped to suit individual conditions. In the illustrated example the surface is cylindrical so that its inclination increases in forward direction (FIG. 5).

An elbow lever 47 is swingably mounted by means of a bolt 46 on the forward end of the arm 3 between the flanges 12 and has two separate lower portions 48 (FIG. 3) which extend laterally of the pressure roll holder 26. A spring 49 effects abutment of the elbow lever 47 against a forward portion 50 of a bearing for a clearer roller, not shown. The top of the pressure roll holder 26 is provided with laterally protruding shoulders 51 which are abutted by the lower portions 48 of the elbow lever 47 when the latter is swung counterclockwise, as seen in FIG. 4, so that the holder 26 is lifted upon continued counterclockwise swinging of the elbow lever 47. This facilitates removal of the pressure roll 43 from the holder 26 in a forward and downward direction without lifting the guide and weighting arm and without taking the pressure off the top rolls. A removed pressure roll 43 is shown in dashdot lines in FIG. 4.

In FIGS. 3 and 4 an upper apron 52 and a cradle 53 is shown. The forward part of the cradle is pressed down by the rear portion 56 of a spring extending into a cavity 54 in the pressure roll holder 26. The spring has a second end portion 55 which retains the first top roll in the holder 26. In a drafting device having no cradle for an apron, the rear portion 56 of the spring is omitted. The top roll guide and retainer is the same for both apron and non-apron drafting devices. FIG. 6 shows an arrangement in which an element 57 1s longitudinally adjustably connected to the rail 33 and swingably supports a pressure roll assembly 58 which is alike the assembly swingably supported by the element 21 which is shown in FIGS. 1 and 4. The embodiment shown in FIG. 6 is part of a four roll drawing or drafting frame. The bottom rolls shown in FIG. 6 replace the third roll shown in FIG. 1.

I claim:

1. A guide and weighting apparatus for the top rolls of a drafting arrangement of a spinning machine, includmg a frame, an arm swingably connected to said frame, locking means operatively connected to said frame and to said arm for locking said arm in the operating position and permitting upward swinging of said arm out of the operating position, a weighting lever having a substantial portion located within said arm, said weighting lever having a fore end and a rear end, first top roll guide means swingably connected to said fore end, second top roll guide means, a link having a first end pivotally connected to said second top roll guide means, said link having a second end pivotally connected to an intermediate part of said lever, said link being swingably connected to said arrn to swing on an axis which is parallel to and spaced from the pivot axes of said pivotal connections, pressure producing means mounted on said frame, and pressure transmitting means engaging said pressure producing means and movably connected to said frame, the rear end of said lever resting on said pressure transmitting means for receiving the pressure transmitted by said transmitting means.

2. A guide and weighting apparatus as defined in claim 1 and wherein means are operatively connected to said link, to said second top roll guide means and to said arm for guiding said second top roll guide means to move parallel to itself upon swinging of said link on said arm.

3. A guide and weighting apparatus as defined in claim 1 and wherein said second top roll guide means includes a rail and a top roll holder mounted on said rail, said rail being pivotally connected to said link, and wherein an element is pivotally connected to said link and has ends individually swingably and slidably connected to said rail and to said arm to slide in a direction parallel to the longitudinal axis of said rail for guiding said rail to move parallel to itself upon swinging of said link on said arm.

4. A guide and weighting apparatus as defined in claim 1 and wherein said second 'top roll guide means includes a rail pivotally connected to said link, means operatively connected to said link, to said rail and to said arm and constructed and arranged so as to guide said rail to move parallel to itself upon swinging of said link on said arm, and a top roll holder supported by said rail and adapted to be displaced longitudinally of said rail.

5. A guide and weighting apparatus as defined in claim 1 and wherein a bracket is connected to said arm and displaceable longitudinally of said arm for adjusting the position of said bracket relative to said arm, and said link is swingably connected to said bracket.

6. A guide and weighting apparatus according to claim 5 and wherein said pressure transmitting means include pressure compensating means for maintaining constant the pressure received by the rear end of said weighting lever when the position of the latter relative to said pressure transmitting means is changed.

7. A guide and weighting apparatus according to claim 5 wherein said pressure transmitting means includes a pressure transmitting lever swingably connected to said frame and having a rearwardly extending arm acted upon by said pressure producing means and having a surface on which the rear end of said weighting lever rests, said surface being forwardly and downwardly curved to provide an increasing decline of the surface for compensating the increase of the force acting on the rear end of said Weighting lever when the latter is moved forward.

8. A guide and weighting apparatus as defined in claim 1 wherein said first top roll guide means includes an element swingably supported by said weighting lever, a spindle longitudinally displaceable in and supported by said element, a fore top roll holder supported by said spindle forward of said element, a second top roll holder supported by said spindle in the rear of said element, said second holder being longitudinally displaceable on said spindle for changing the spacing between said holders; said spindle, said element, and said second holder including means for maintaining the leverage relation of said holders with respect to the swing fulcrum of said element when the spacing between the holders is changed.

9. A guide and weighting apparatus according to claim 8 including means swingably connected to said arm and adapted to engage said fore top roll holder for lifting the latter when said arm is locked in the operating position to permit removal of the fore roll from the fore holder.

10. A guide and weighting apparatus according to claim 9 and wherein said fore top roll holder is provided with a shoulder and said means which are swingably eonneeted to said arm are in the form of an elbow lever having an arm adapted to abut said shoulder.

11. A guide and weighting apparatus as defined in claim 1 and wherein said second top roll guide means includes a rail pivotally connected to said link, means operatively connected to said link, to said rail and to said arm for guiding said rail to move parallel to itself upon swinging of said link on said arm, an element swingably connected to said rail, a spindle extending through said element and being longitudinally displaceable therein, a first top roll holder supported by said spindle forward of said element, a second top roll holder supported by said spindle rearward of said element, one of said holders being longitudinally displaceable on said spindle for changing the spacing between said holders; said spindle, said element, and said displaceable holder including means for maintaining the leverage relation of said holders with respect to the swing fulcrum of said element when the spacing between the holders is changed.

No references cited. 

1. A GUIDE AND WEIGHTING APPARATUS FOR THE TOP ROLLS OF A DRAFTING ARRANGEMENT OF A SPINNING MACHINE, INCLUDING A FRAME, AN ARM SWINGABLY CONNECTED TO SAID FRAME, LOCKING MEANS OPERATIVELY CONNECTED TO SAID FRAME AND TO SAID ARM FOR LOCKING SAID ARM IN THE OPERATING POSITION AND PERMITTING UPWARD SWINGING OF SAID ARM OUT OF THE OPERATING POSITION, A WEIGHTING LEVER HAVING A SUBSTANTIAL PORTION LOCATED WITHIN SAID ARM, SAID WEIGHTING LEVER HAVING A FORE END AND A REAR END, FIRST TOP ROLL GUIDE MEANS SWINGABLY CONNECTED TO SAID FORE END, SECOND TOP ROLL GUIDE MEANS, A LINK HAVING A FIRST END PIVOTALLY CONNECTED TO SAID SECOND TOP ROLL GUIDE MEANS, SAID LINK HAVING A SECOND END PIVOTALLY CONNECTED TO AN INTERMEDIATE PART OF SAID LEVER, SAID LINK BEING SWINGABLY CONNECTED TO SAID ARM TO SWING ON AN AXIS WHICH IS PARALLEL TO AND SPACED FROM THE PIVOT AXES OF SAID PIVOTAL CONNECTIONS, PRESSURE PRODUCING MEANS MOUNTED ON SAID FRAME, AND PRESSURE TRANSMITTING MEANS ENGAGING SAID PRESSURE PRODUCING MEANS AND MOVABLY CONNECTED TO SAID FRAME, THE REAR END OF SAID LEVER RESTING ON SAID PRESSURE TRANSMITTING MEANS FOR RECEIVING THE PRESSURE TRANSMITTED BY SAID TRANSMITTING MEANS. 